1. Field of the Invention
This invention relates generally to a system for identifying and locating an object. More specifically, but not by way of limitation, this invention relates to an electronic system utilizing one or more sensors to measure the motion of an object and augment satellite position data obtained with known satellite positioning methods.
2. Brief Description of Related Art
In recent years, numerous systems and methods have been proposed and developed for tracking the location of an object. Larger, more expensive systems exist for tracking the position of delivery trucks and the like. These systems largely rely on vehicle power systems and are thus poorly suited to use on smaller objects.
One especially problematic application of such a system is for tracking relatively small objects or animals, such as domestic pets, hunting dogs, or livestock, which may move in a nearly infinite combination of directions and distances. Several systems have been created to address this specific application.
These systems utilize a variety of methods to track an object's position. One such system measures the relative strength of a radio frequency signal emitted from a transponder attached to the object to determine a direction and approximate distance from the transponder to a display unit. Another system utilizes a GPS (Global Positioning System) receiver to obtain the object's position and transmits the position data to a display unit. Yet another positioning system utilizes a GPS receiver to obtain the object's position, as well as a compass to determine the object's orientation. These GPS systems then use existing telephonic cellular and paging networks to transmit the object's location information to a display unit such as a cellular phone or computer.
Several significant problems remain with the above mentioned systems. Measuring the strength of radio frequencies is relatively inaccurate and makes it extremely difficult to calculate or display direction of travel. Further, radio frequency systems are not well suited to differentiating between multiple objects or uniquely identifying such objects.
Positioning systems which rely solely on GPS or other satellite data are susceptible to inconsistent performance in treed or overgrown areas where the GPS receiver cannot maintain simultaneous line-of-sight communication with at least three satellites. Systems mounted on shorter animals, such as hunting dogs, are even more susceptible to interruption since bushes and tall grasses may obscure the GPS receiver.
Thus, there exists a need for a position tracking system which can track changes in position and augment GPS position with locally-measured data to more reliably track the position of an object. There exists a further need for a tracking system which can monitor the position of multiple objects while allowing the user to differentiate between them.
Other features, advantages, and objects of the present embodiment will become apparent to those of at least ordinary skill in the art when the following description is read in light of the attached drawings and appended claims.